Tuyere block



April 23 1929 Q JOHNSON 1,710,260

TUYERE BLOCK Filed June 22, 1925 INVENTOR Oscar H. Johnson ATTQRN Y Patented App 23, 1929,

UNITED STATES PATENT OFFICE.

'OSCAR A. JOHNSON, OF WORCESTER, MASSACHUSETTS,' ASSIGNOR TO RILEY STOKER CORPORATION, OF WORCESTER, MASSACHUSETTS, A CORPORATION OFMASSACHU- SETTS.

TUYERE BLocK.

Application filed June 22, 1925. Serial No. 38,707.

My invention relates to underfeed stokers and more particularly to a tuyere block structure adapted to serve as a grate block to support the fuel bed and to admit air thereto.

An underfeed stoker comprises a deep retort located between side walls surmounted by tuyere blocks which are arranged to transmit air from a passage beneath the retort to the fuel bed. One form of tuyere struc ture consists of narrow blocks mounted side by side in such a manner that they can be easily replaced, Since these blocks are exposed to the intense heat of the burning fuel, they are-ordinarily made of a vertical web portion having an outer flange supporting the fuel and ribs on the side of the web so arranged as to provide grooves therebetween which form tuyere openings between adjacent blocks.

The tuyere blocks as previously construct.

ed have been so made that when the outer flange has been burned through, a hole is thus formed which communicates with the air passage beneath and lets a large volume of air escape into the fuel bed and thusdetracts from the efiiciency of operation of the fuel to furnace. Also this hole permits the fall into the air passage; K

It "is accordingly the mainobject of my invention to overcome this difiicu'lty and to provide a tuyere block which is so constructed and arranged that it will havea long and ellicient life and provide a substantially uniform y flange 22 extending along its upper and outer tuyere opening for the pasage of" air even after the block has been burned away, to a.

considerable extent,

With this and otherob ects in view 'as iu .be-apparent to one skilled inthe art, myin 'vention resides in thecombination of parts set forth in the specification and covered by the claims appended hereto. 3

Referring to the drawings which illustrate one embodiment of my invention 1 Fi 1 shows somewhat diagrammatically. and partly broken away'a single retort stoker having side dumping plates and tuyere blocks embodying my invention; and

Fig. 2 shows in perspective viewja group of tuyere blocksassembled in proper relation to each other.-

In accordance with myv invention, I so form the tuyere block as to provide, in addition to the usual fuel supporting flange, a

adjacent secondary flanged or ribbed structure which Wlll serve as a fuel support when the upper flange has been burned away, and which will ma ntain substantially the same area of air openings to the fuel as existed originally, thereby prolonging the useful life of the block.

Qne typeof underfeed retort stoker to wh ch this invention may be applied compr1ses, as shown in Fig. 1, walls 10 which form a substantially U-shaped retort within which fuel may be suitably fed from outside the furnace. mounted on a suitable foundation 11 and spaced from the furnace. walls 12 on both "sides to provide room for the grate structure and dumping plates. A partition Wall 13 is provided on each side of the retort, but.

one of which is shown, and the dumping The retort walls are means of a suitably arranged hinge structure In the construction illustrated the retort/walls" lOare turned over at their tops to form substantially horizontal plate poi tions 16. Removable dead plates 17 are supported on the outer ends of these plates 1G and the tops of the walls 13.

In order to admit air to the fuel and to support the fuel bed at the sides of the retort adjacentth'efhot zone of the fire, the tuyere blocks 20er provided. As illustrated, a block, which embodies my invention, com-'1 prises a central vertical web 21' having a wide edges'to support the fuel bed, and this'flango spaced and arranged that air may pass bethe air chamber beneath the tween them from blocks to the fuel bed. The ribs 23 form the bottom of themain portion of the block and are arranged to rest on the top corner portion 26 of the wall 10. The sides of the ribs 23 of blocks contact with each other and thus forma continuous surface touching the .isso constructed and arranged thatadjace'nt I i retort top which prevents theleakage ofair at this point and a consequent burning of the retort. Q The ribs 24 and 25"are arranged pref erably parallel with the ribs 23, and they are all'horizontallyor otherwise disposed so that 1 rib 25 verylong, wherebya sp'ace28 is formed which commiinicates' with the outerends of the passages betweenthe ribs. The passages.

between these ribs are suitably proportioned ,andshaped as desired to furnish the'required amounts of air at the tuyere openings '30, 31

and-32 which communicate with the fuel'bed.

It will also .be apparent that the sides of the .ribs and flanges aregformed in substantially thesame plane, or otherwise arranged so that 2o adj acent'blocks will fit against one another to form spaced tuyere openings and substantially-eontinuous surfaces lying. in'contact with the fuel.

The top rib v is substantially coextensive 25 with the top flange 22 but is slightly shorter than the block, so as to leave a space between the outer end" 33 of this rib and the vertical flanged portion 34 on the outside of the block. This space/is substantially equal to the width aoof the air channel between flange 22 and rib 25. It will therefore be seen that this arrangement is such that the top flange, the web position shown approximately by the line 35 'aa without changing materially the size of the air openings tothe fuel bed. Also, the top flange 22 may burn away until it reaches the outer end 33 of the rib 25 before fuel can escape downwardly through the tuyere open;

0 ings. This construction is'therefore one in which the ribs 2 fgglconstitutes a secondary flange or supplementary I fuel, supporting structure for usef'as the upper flange-burns "away, j1he-"iuyere 'assages between the other ribs are prefra ly provided with par; allel walls so that the tuyere' openings do not cliangein' size.'. 7 7 p,

" The blocks may 'bexsuitably fastened-in place, as by nieans'of the dcpe'nding portions 36 which are provided with apertures ar ranged-to; permitthe passage of a rod 37.the1'-ethrough, this rod being adapted to besuitably fastened to the stoke-r parts tohold the tuyere' blocks in position. The depending portion 36 of the tueyre block passes'through an open-- ing 38 suitably formed in the flat plate 16. y

In view of the above disclosure,it will now be seen that this invention is equally applic able totuyere blocksused in other portions of -the furnace, such as adjacent the side walls of thefurnace, or between adjacent retorts, or wherever it is necessary to support the fuel and admit air' thereto. This construction is such that one may secure satisfactory combustion within the stoker for a longer length of time than heretofore obtainable with tu yere blocks of this type. During the effective life of the block, the tuyere openings remaln substantially uniform in area, and fuel cannot sift through them into the air chamber beneath the retort; This construction increases the efliciency of the stoker in that it prevents the formation ofblow holes in the fire. Also, an additional cooling surface on the tuyere plates is provided by the use of these long ribs of such-extensivesurface.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent is:

1. A tuyere block comprising a thin web adapted tobe mounted vertically on a stoker,

a laterally projecting, fuel supporting flange of substantially uniform width on the upper edge of the web and a set of spaced ribs projecting laterally from one side of the web to form tuyere channels, the upper rib extending throughout the major portion of the length of the block and cooperating with the flange to form a long, narrow tuyere channel and a secondary fuel support.

2. A tuyere block comprising a thin web adaptedto be mounted vertically on a stok'er,

a fuel supporting flange extending along the top edge of the web, a top rib on the side of the web substantially coextensive and parallel with the flange which serves as a secondary fuel support and cooperates with the flange portion and the ribs may all. burn away to a adapted to be mounted vertically on a stoker,

a" flange on the top edge of the web, a set of spaced ribs on one side'of the web which form tuyere channels leading to tuy eres on one end of the block and a flange on the opposite end of the block from. the tuyeres, the top rib extending from the tuycre end nearly to the end flange and cooperating with both flanges to form a long, narrow channel having an inlet near the end flange which controls the flow of air through the channel.

.4. A tuyere block comprising a thin web adapted to be mounted vertically on a stoker,

a fuel supporting flange of uniform width on the to of the web and projecting laterally from 0th sides thereof and a set of spaced ribs on each side ofthe web ,which cooperate.-

to form tuyere channels, the top ribs being substantially horizontal throughout the major portion of the length of the block to form a secondary fuel support.

5. A tuyere block comprising a web adapted to "be mounted vertically on a stoker, a laterally extending, fuel supporting flange on the topedge of the web, a. top rib on the web which is spaced from the flange and extends and extending throughout the major portion of the length of the block to form a secondary fuel support and a long tuyere channel, and long spaced ribs beneath the top rib which form further seclondary fuel supports and long tuyere channe s.

6. A tuyere block comprising a thin Web arranged to be mounted in a stoker vertically above an air passage, a flange on the upper edge of the web having a top arranged to support the fuel and ribs on the side of the Web extending inwardly from the tuyere edge of the block for progressively increasing distances from the lowermost to the top rib, said flange and ribs cooperating to form tuyere channels, the inlet ends of which are substantially horizontally spaced and directly receive the air ascending thereto from said passage, and the top rib extending throughout the major portion of the length of the block.

7. A tuyere block comprising a thin web adapted to be mounted vertically on a retort Wall, a flange along the top, a substantially vertical flange on one end of the Web, a series of long spaced ribs substantially parallel with the top flange which extend from the end of the Web opposite the vertical flange but are progressively shorter in length from the top to the bottom of the block, tr e upper rib extending nearly to the vertical flange and being so arranged relative to the top flange as to form a narrow tuyere channel and to serve as a secondary fuel support.

Signed at Worcester, Massachusetts, this 15th day of June, 1925.

OSCAR A. JOHNSON. 

